Orion 8" f/8 Ritchey Chretien Reflecting OTA Telescope

8" (200mm) aperture Ritchey Chretien optical tube ideal for use with DSLR cameras and small-format CCDs to produce wonderfully flat, virtually coma-free astrophotos Hyperbolic primary and secondary mirrors made of low-expansion quartz glass with enhanced aluminum coatings boast 96% reflectivity for bright imaging performance, and the secondary mirror is precisely center-marked to aid in collimation A rotatable, machined dual-speed (10:1) Crayford focuser equipped with a sturdy linear-bearing provides precise focus adjustment without slippage or flexure with heavy astrophotography accessories attached Three included focus extension rings (one 2" and two 1") allow focus position adjustment for use with various imaging cameras and astrophotography accessories Features two dovetail finder scope bases and a unique, Orion-exclusive slotted narrow dovetail bar along the top of the tube for easy accessory attachment Orion 8" f/8 Ritchey-Chrétien Astrograph Telescope with 2" dual-speed lin